update the example

Author: woss

README.md

@@ -5,3 +5,7 @@ Sharp js as a layer,
 ## Image copyright
 
 `lucky.jpg` is owned by me
+
+## Example
+
+http://0.0.0.0:4000/sharp?width=800&metadata=true&convolve=true

example/src/handler.js

@@ -1,27 +1,53 @@
 const sharp = require('sharp')
 const path = require('path')
+const fs = require('fs')
 
 exports.handler = async event => {
   try {
+    // Read the file to a buffer
     const imagePath = path.resolve('./src/lucky.jpg')
-    console.log(imagePath)
-    const img = await sharp(imagePath)
-      .withMetadata()
-      .resize(800)
-      .convolve({
+    const imgBuf = fs.readFileSync(imagePath)
+
+    // Extract the qs from the event
+    const { queryStringParameters } = event
+    console.log(`Got query params `, queryStringParameters)
+    const { width, height, metadata, convolve } = queryStringParameters
+
+    // Let's create the sharp instance
+    const img = sharp(imgBuf)
+
+    if (metadata === 'true') {
+      img.withMetadata()
+    }
+
+    img.resize({
+      width: parseInt(width, 10) || 800,
+      height: parseInt(height, 10),
+      fit: sharp.fit.cover,
+      position: sharp.strategy.entropy
+    })
+
+    // for fun of it 😎
+    if (convolve === 'true') {
+      img.convolve({
         width: 3,
         height: 3,
         kernel: [-1, 0, 1, -2, 0, 2, -1, 0, 1]
       })
-      .webp()
-      .toBuffer()
+    }
+
+    // transform to the webp format
+    img.webp()
+
+    // last thing is to get the buffer of cloned instance
+    const image = await img.clone().toBuffer()
 
     const response = {
       statusCode: 200,
       headers: {
         'Content-Type': 'image/webp'
       },
-      body: img.toString('base64'),
+      body: image.toString('base64'),
       isBase64Encoded: true
     }
     return response